Renovation obligation after buying a home in Belgium: deadlines by region and the works that gain the most label letters
Short answer: Only Flanders currently requires renovation after a purchase: a home with EPC label E or F must reach at least label D within six years of the notarial deed. Brussels sets a fixed deadline for all homes (275 kWh/m² by 1 January 2033). In Wallonia, an obligation on purchase is still a draft. Roof and wall insulation deliver the biggest energy gain; solar panels give the quickest gain on the EPC score.
Prices in this article are indicative Belgian market ranges, not Alpha Services Benelux's price list. Your fixed price is in the quote.
What applies after a purchase in each region?
Only Flanders obliges you to renovate after buying today; Brussels sets a fixed deadline for all homes and Wallonia has nothing binding yet. The table summarises the official regional pages and the Certinergie overview (status 16 October 2026).
| Region | Tied to purchase? | What and when | Status |
|---|---|---|---|
| Flanders | Yes | House or flat with EPC label E or F: at least label D within 6 years of the notarial deed | In force |
| Brussels | No | All homes: maximum 275 kWh/m² per year (about class E) by 1 January 2033 at the latest; 150 kWh/m² per year (about class C) at the earliest on 31 December 2045 | 2033: set; 2045: date still to be fixed by the government |
| Wallonia | Planned | Draft: 5 years after the deed, label D for deeds from 2028, C from 2031, B from 2036, A from 2041 | Draft, not voted |
This table is not legal advice: the texts can still change, so always confirm with the competent authority.
Flanders: six years to go from E or F to D
In Flanders, the buyer of a home with EPC label E or F must reach at least label D within six years of the date of the authentic deed. vlaanderen.be gives this example: a deed dated 1 February 2023 means the obligation must be met by 1 February 2028 (the earlier five-year period). Vlaanderen.be states six years; according to Certinergie (decision of 12 December 2025), this has applied since 1 January 2026, including for deeds signed since 2023. Confirm your own end date with VEKA.
- Proof: a new EPC issued by an accredited energy expert.
- Reference point: the condition of the home at the time of the deed counts, not your future plans.
- Enforcement: sanctions are possible in case of non-compliance; ask the Flemish Energy and Climate Agency (VEKA) about the consequences.
The vlaanderen.be page also lists later tightening steps (label C from 2028, up to A). Certinergie reports that the 2024-2029 government agreement dropped them. Do not base any decision beyond label D without confirmation from VEKA.
Brussels and Wallonia: no purchase trigger, but a direction of travel
Brussels does not look at when you buy but at the year: by 2033 every home must stay under 275 kWh/m² per year. Bruxelles Environnement gives 31 December 2045 at the earliest for the next level (150 kWh/m², about class C); the government still has to fix that date. Derogations are possible under conditions (technical, functional or economic reasons, or heritage); check the conditions with Bruxelles Environnement/Homegrade. Bruxelles Environnement mentions administrative fines and/or criminal sanctions for non-compliance with PEB rules; ask Bruxelles Environnement about the concrete consequences for the 2033 target.
In Wallonia, no obligation after purchase exists today. The government approved a draft renovation plan in December 2025. It foresees 5 years after the deed to reach label D (deeds from 2028), C (from 2031), B (from 2036) or A (from 2041). The European Commission still has to validate it (final version expected in December 2026), followed by a decree and implementing orders. According to Certinergie, no sanction is foreseen for this calendar.
Buying in Brussels or Wallonia? Insulating thoroughly now will probably put you in good shape for this trajectory, but that remains an estimate.
Which works gain the most label letters?
In Immoweb's analysis, solar panels give the quickest gain on the EPC score (38%), but roof insulation delivers by far the biggest energy gain (155 kWh/m² per year). On the EPC score, wall insulation (34%), roof insulation (31%) and a heat pump (29%) follow. The figures come from an audit of 32 homes of 200-250 m² (ImmoPass, 2024) and depend heavily on the starting condition.
| Measure | Gain on EPC score | Energy gain (kWh/m² per year) |
|---|---|---|
| Wall insulation | 34% | 99 |
| Roof insulation | 31% | 155 |
| Solar panels | 38% | 41 |
| Heat pump | 29% | 67 |
| Floor insulation | 17% | 34 |
| Ventilation with heat recovery | 16% | 23 |
| Windows | 9% | 25 |
| Heat pump water heater | 8% | 9 |
A different yardstick is gain per euro invested. There Van Marcke puts roof insulation first, then walls, with floor insulation usually last; a heat pump is often the strongest single measure. Have an energy expert calculate your own home: a house with single glazing or an old boiler behaves differently from a newer one.
For the logical order of works, see insulate first or heat pump first.
What do these works cost?
According to Isolatie-info.be (incl. VAT), insulation costs from 15 euros per m² for cavity wall to 155 euros per m² for a rendered (crepi) facade; a heat pump or ventilation system is a line item of several thousand euros. These are Belgian market prices from published price guides, not a price list of ours. The sources differ: one quotes prices including VAT, the other excluding VAT. We therefore show them side by side rather than merging them.
| Work | Isolatie-info.be (incl. VAT) | Batibouw+ (excl. VAT) |
|---|---|---|
| Pitched roof, from inside | 30 to 65 euros (excl. finishing) | 25 to 55 euros |
| Pitched roof, from outside (sarking) | 50 to 120 euros (excl. finishing) | 60 to 110 euros |
| Loft floor | 25 to 50 euros | 15 to 35 euros |
| Cavity wall | 15 to 35 euros | not stated |
| External facade in render (crepi) | 120 to 155 euros | not stated |
| Work | Range | Source and basis |
|---|---|---|
| HR++ glass in existing frame | 80 to 130 euros per m² | Energiebewust ontwerpen, installed, excl. VAT |
| Triple glazing (HR+++) | 130 to 220 euros per m² | Energiebewust ontwerpen, glass + installation; usually with new profiles, for an existing frame have it checked first whether the glass thickness fits |
| Air-to-water heat pump | 5,000 to 15,000 euros | Energiebewust ontwerpen |
| Air-to-water heat pump | 8,000 to 18,000 euros | Premie-warmtepomp.be, installation and 6% VAT included |
| Ventilation system D | 4,000 to 9,000 euros | Facq; Premie-berekenen.be gives 4,000-8,000 |
The differences between sources reflect capacity, home size, finish level and whether VAT and installation are included.
What drives the price and the label gain?
The starting condition of the home drives both the cost and the gain: the worse the starting point, the more each measure delivers. Five factors weigh most:
- Technique: sarking (from outside) costs more than insulating between the rafters, because tiles, battens and underlay often have to be removed and refitted.
- Finishing: on roofs, interior finishing is often not in the base price; on facades, the price climbs from render (120 to 155 euros per m² according to Isolatie-info.be) to brick slips or facing brick.
- Capacity and hydraulics: for a heat pump, capacity and the adaptation of the heat-emission system make up a large part of the bill.
- Size and accessibility: number of windows, pipe length, roof access.
- Asbestos or hidden defects: Batibouw+ cites an extra 15 to 25 euros per m² when asbestos (roofs from before 1998) has to be removed during sarking.
Comparing quotes and avoiding surprises
After buying, start with an EPC analysis, then request quotes on the same basis and let one party manage the sequence. That way the measures do not work against each other.
- Have the current certificate and a renovation advice drawn up by an accredited energy expert, and note the end date of your deadline.
- Ask for written quotes with the same thickness, material and finish; check whether prices include or exclude VAT.
- Have the quote state what is included: demolition, scaffolding, interior finishing, waste removal.
- Schedule the new certificate well before the deadline so you can still adjust.
- Check your region's official portals (vlaanderen.be/mijn-verbouwpremie, renolution.brussels, wallonie.be) before signing.
Alpha Services Benelux (active since 2014) carries out renovation work with its own team and gives a fixed written quote after a site visit. Renovation is by appointment. Call or WhatsApp 0485 44 55 12 or email [email protected], or start with the renovation calculator (in Dutch) and our renovation page.
Fixed quote after a site visit
Alpha Services Benelux does the work with its own team, active since 2014. VAT BE 0541.320.178.
Request a quoteFrequently asked questions
Do I have to renovate if I buy an EPC E or F home in Flanders?
Yes. You must reach at least label D within six years of the date of the notarial deed and prove it with a new EPC. Vlaanderen.be states six years; according to Certinergie this has applied since 1 January 2026 (previously five), also for deeds since 2023. Confirm your own end date with VEKA.
Does the renovation obligation also apply in Brussels?
Not as a purchase obligation. Brussels does set a fixed deadline for all homes: a maximum of 275 kWh/m² per year (about class E) by 1 January 2033. For 150 kWh/m² per year the date is 31 December 2045 at the earliest and still has to be fixed by the government. Derogations are possible under conditions.
Is there a renovation obligation after purchase in Wallonia?
Not yet. A draft plan foresees five years after the deed to reach label D for deeds from 2028, then C from 2031, B from 2036 and A from 2041. It awaits European Commission validation, a decree and implementing orders.
Which works improve my EPC the most?
In Immoweb's analysis of 32 homes, solar panels gave the biggest gain on the EPC score (38%), followed by wall insulation (34%), roof insulation (31%) and a heat pump (29%). Windows followed with 9%. In energy saved, roof insulation leads with 155 kWh/m² per year, almost four times solar panels. Results depend on your home's starting condition.
How much does roof insulation cost to improve my label?
For a pitched roof from inside, Isolatie-info.be cites 30 to 65 euros per m² (incl. VAT, excl. finishing) and Batibouw+ 25 to 55 euros per m² (excl. VAT). From outside (sarking), the range rises to 50 to 120 euros depending on source and finish.
What happens if I miss the deadline in Flanders?
Sanctions are possible in case of non-compliance. Confirm the concrete consequences, the amount and the procedure with the Flemish Energy and Climate Agency (VEKA).
Sources
- Renovation obligation for residential buildings — Vlaanderen.be (Flemish government)
- Objectifs PEB pour chaque logement et exigences PEB en cas de travaux — Bruxelles Environnement
- Calendrier PEB 2026-2050 : obligations en Wallonie, Bruxelles et Flandre (situation au 16 octobre 2026) — Certinergie (cites SPW Énergie, Vlaanderen.be and Bruxelles Environnement)
- Rénovation du bâti en Wallonie : le Gouvernement wallon pose un cadre général — SPW Énergie (Wallonie)
- Je EPC-score verbeteren: welke renovatie-ingreep zorgt voor de grootste boost? — Immoweb (data ImmoPass, 32 homes, published 7 Aug 2024, updated 19 Aug 2024)
- EPC-waarde verbeteren: welke ingreep levert het meeste op per geïnvesteerde euro? — Van Marcke (2026)
- Isolatie prijzen 2026: per m², per toepassing — Isolatie-info.be (Solvari), 2026
- Dakisolatie in België 2026 — Batibouw+ (2026)
- Hoogrendementsglas (HR++): besparing, prijzen & premies 2026 — Energiebewust ontwerpen (2026)
- Prijs warmtepomp 2026: kosten, premies, terugverdientijd — Energiebewust ontwerpen (2026)
- Prijs warmtepomp 2026: wat kost een warmtepomp in België? — Premie-warmtepomp.be (2026)
- Dual-flow ventilation in Belgium: actual savings and return on investment (2026) — Facq (2026)
- Premie ventilatiesysteem 2026 — Premie-berekenen.be (2026)